Fuze safety devices of the above-mentioned type are well known in the art. A fuze may for instance be armed by means of a slide member comprising a primer charge displaceable from a safe to an armed position under the influence of an external force caused, for instance, by the spinning of the ammunition unit.
Prior to firing of the ammunition unit the movement of the slide member is usually prevented by three locking elements: an axial locking member, a centrifugal locking member and an arming locking member, each of which is able to prevent the slide member from assuming its second, armed position. The axial and centrifugal locking members are released by acceleration and rotation, respectively, but the arming locking member can be released by a timer.